Thread: ITB build v1 (dyno inside)

I've completed my ITB build at August, but was too busy to tune it. So, now I have a time to share my findings with the community.

ITB setup shows a massive 15hp rise on wide rpm range.



My setup was: 20V motor, 12:1 CR, 20V/FS4 cams, 20V header, 80mm exhaust. The only difference was 20V intake vs ITB intake. Cams tuned slightly for each setup. Best cams switch point moved from 6200 on 20V intake to 5000 on ITBs.

My ITBs are built from Hayabusa 45mm ones on stripped 20V intake collector joined with original Hayabusa rubber joints.






This summer build was tuned at the end of September. My engine died the same day it was tuned (to many high rpm runs), so I think the numbers may be even higher on fresh motor.

Look at the pictures, ask a questions.

PS: ITB build v2 will be competed as soon as I restore my engine. 50mm m5 e49 throttles are sitting in my garage.

Wow good stuff man! I bet the 50mms kick ass hopefully hold more power up top. Have you any graphs w these cams vs n 1s?

And really thank you for sharing!

Cory, I never ran n1 cams in this engine, sorry. I have another similar 20VE build here with n1 cams in it, I'll maybe do the test vs n1 cams if I have a time.

Great work. That midrange gain is awesome. It would be nice to see that powerband shift even higher with bigger stacks. Good luck on more gains. What does that torque convert to in wtq?

Nvm, found a converter. 178 ft/lb. Impressive as hell Flywheel hp or not.

Yes, I'm sure. Cause stock 20V intake collector has slim 42mm tubes, the same size have Hayabusa ITBs from the head side (45mm at the butterfly up to 50mm at the intake side), so basically they fit right. But the head's ports have equal diameter of 45 or even 48mm (have no real number with me).

there is no matter of actual numbers, the difference is. I think it's something like 204whp@7880 152lb-ft@6180, but I doubt the actual numbers may be 3-5% higher.

Whatever it may be, the powerband is awesome. I'll keep my eyes peeled on the progress. What are you using to tune?

Any vids? I bet it sounds awesome

i think you would have some better gains if you made a box to go over the hats/bells and designed some sort of intake track for i...this way you could get clean cool air from outside the engine compartment instead of warm to hot air from under the hood